Prior art applied to the recovery of Oil and Oil Products from the surface of both Sea Water and Fresh Water have not addressed the primary problem of the small differences in specific gravity between the water and the organic liquid and the effects of Sun, Wind and Waves on relative small differences that provide for a film of Oil or Oil Product to stay on the surface of the Water. The maximum weight per gallon of Sea Water is 9.0 pounds per gallon, the minimum weight of Fresh Water is 8.33 pounds per gallon and the average weight of Crude Oil and many processed Oil products is 8.2 pounds per gallon.
When the Oil or Oil Product is first discharged into either Sea Water with a weight of 9.0 pounds per gallon, Fresh Water at 8.33 pounds per gallon or Brackish Water with a weight of any where between 8.33 and 9.0 pounds per gallon, there is an adequate difference in specific gravity to provide efficient recovery of the Oil or Oil Products from the surface of the water.
Within a short period of time, dependent on the weather conditions, this opportunity for efficient recovery is lost. This is due to the effect of the Sun and Wind which causes the evaporization of the lighter fractions of the Oil or Oil Product, which results in an increase in its specific gravity. The second factor is the action of Waves which cause a breakdown of the surface tension of the Oil or Oil Product film, coats droplets of the organic material with water; thus causing a further increase in the specific gravity of the Oil or Oil Product. The Oil film very soon becomes a blanket of Oil droplets below the surface of the water phase and cannot be recovered by the application of surface skimming techniques.
Prior art is demonstrated by all of the following references. Surface containment means with surface skimmer as defined in U.S. Pat. No. 4,049,554. Surface containment with air bubble barrier and suction device as defined in U.S. Pat. No. 3,966,613. Surface containment with vacuum suction device as defined in U.S. Pat. No. 3,578,171. Velocity surface skimmers as defined in U.S. Pat. Nos. 3,737,040, 3,690,464, 3,875,062 and 3,823,828, Rotating Drums as defined in U.S. Pat. Nos. 3,753,496 and 3,853,767. Enless Belts as defined in U.S. Pat. Nos. 3,314,540 and 3,314,545. Stationary pressure differential systems as defined in U.S. Pat. Nos. 3,465,882, 3,615,017, 3,715,034 and 3,966,615. All of this prior art does not address the major problem of sub-surface Oil droplets.
The second consideration defined in the background of the invention is the effect of waves on the Oil film on the surface of the Water. Prior art has addressed this problem in the main by the use of internal tanks in a vessel and ballast tanks for adjustment of the pitch and the depth of the vessel. Internal tanks with ballast tanks for the adjustment of pitch and depth are defined in U.S. Pat. No. 3,630,376. Multiple interior tanks in a vessel for the separation and concentration of the skimmer Oil are defined in U.S. Pat. Nos. 4,399,040, 4,477,348 and 3,922,225. This approach has not provided an efficient solution to the problem of collecting Oil from the surface of water.
Prior art concerning on board concentration of the captured Oil is defined in U.S. Pat. Nos. 4,795,567, 3,578,171, 3,219,190, 4,178,247 and 3,578,171. None of the above systems have proven to be efficient in the on board concentration of skimmed Oil due primarily to batch or multiple batch operation in place of continuous operation.
The Barge Mounted Oil Recovery and Recycle System addresses the problem of subsurface Oil droplets and provides a method for the immediate start of recovery operation to minimize the effect of time on the physical properties of the Oil Film. The Barge Mounted Oil Recovery and Recycle process also provides a high efficiency continuous on board concentration process for the Oil/Water mixture received from the collection processes.